The Logarithmic Wind Profile

This paper explores the practical consequences of the asymptotic nature of the logarithmic wind profile in neutral, barotropic, planetary boundary layers. Recent developments in boundary-layer theory have shown that the von Kármán constant is a universal constant only in a very specific asymptotic sense; in typical atmospheric conditions its value is probably about 10% larger than the asymptotic one. Pending the development of a second-order theory, the value κ = 0.35 ± 0.02 is recommended for micrometeorological applications over smooth terrain. It is shown that K theory cannot be used in attempts to detect any trends of deviations from the logarithmic law.